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Despite having some trouble with maneuvering thrusters a few days ago, SpaceX's Dragon cargo capsule has successfully reached the International Space Station. from the article: "Astronauts aboard the outpost used the station's robotic arm to pluck the capsule from orbit at 5:31 a.m. EST as the ships sailed 250 miles over northern Ukraine. Flight controllers at NASA's Mission Control in Houston then stepped in to drive the capsule to its berthing port on the station's Harmony connecting node."

I don't see why you disagree. In many cases, the "load" is the trailer. And so, yes, truckers do leave the trailer behind on trips, throwing away the cargo container with shipments. I've seen people in rural Alaska make houses from the containers that things come it. It's cheaper than paying to ship them back once delivered.

I've seen people in rural Alaska make houses from the containers that things come it. It's cheaper than paying to ship them back once delivered.

In most of the coastal USA you can get a container of varying description delivered for $2-5k, sometimes including long and tall refrigerated units. They might be even cheaper in Alaska, which has few exports that cannot be shipped by pipeline or jet stream. They're literally a problem at some ports.

Much of rural Alaska gets one barge a year that doesn't stay long enough to pick up the empties. Either you store them for a year and pay to ship them out (maybe fill them trash), or build with them. No idea what they cost, but they are not uncommonly turned into buildings, or parts thereof.

Well, they're probably pretty cheap any time the population isn't growing, but I only have specific knowledge of what it costs to get them delivered in nocal. They probably still cost money in the midwest, which still exports some stuff in them. They are probably damned near free in LA.

If it's so insanely expensive and difficult, then why is SpaceX working on just that, a reusable rocket? The pie-in-the-sky has always been a readily reusable rocket. That was the idea behind the shuttle. Didn't work out so well, but that was the idea.

The problem is, re-usability is tough when you are dealing with the extreme requirements of space travel. Noone has proven it to be viable in cost yet, the shuttle shown it was possible though at a expensive cost. SpaceX is not reusable *yet* but their rocket is designed to be. Time will only tell if they succeed. Even Musk acknowledges that it may not be fully reusable (the difficulty of getting the 2nd stage rocket back) as Rocketry is HARD. But you gotta applaud them in their efforts and success will he

Get your facts straight. The SpaceX rocket is not reusable, nor is it designed to be. It is a throw-away. However, the Dragon Capsule, which sits atop the Falcon 9 rocket, is designed to be reusable. Nevertheless, the contract with NASA calls for a new caspule each time.

Having said that, SpaceX *is* working on a rocket where the first stage is reusable. However, that is a few design generations away. They are currently working out the kinks on a test-bed rocket system called Grasshopper. Grasshoppe

You get your facts straight. Yes it was designed to be reusable, from the beginning.

The original plan was to put parachutes on the first stage and use a boat to recover it after ocean splashdown. SpaceX did in fact recover a first stage in service of that plan. There's pictures on the SpaceX site of the recovery operation. As it turns out, the impact of even a parachute landing does enough mechanical damage, coupled with the corrosive effects of seawater doing chemical damage, that the original reusabil

In short, fuel. Slowing down first before reentering the atmosphere requires an enormous amount of fuel. Not as much as getting up there in the first place, but still so much that it's infeasible to take that much along with you into orbit. The mass of heat shielding to use for atmospheric braking is substantially less than the mass of fuel required for equivalent retro-rocket braking.

If it's so insanely expensive and difficult, then why is SpaceX working on just that, a reusable rocket?

It'll be insanely difficult and expensive right up until SpaceX succeeds with soft-landing a first stage, at which point it will be routine and normal and why isn't everybody doing it?

But of course, we will first have to suffer through the clowns telling us how the first soft-landing was a failure because they had to make two tries to restart the engines after separation, so it landed with dry tanks instead of the 5% safety margin it was supposed to land with so it was a CATASTROPHIC FAILURE. Nevermind the

Actually TFA said "Dragon is the only station freighter that makes return trips", but that doesn't necessarily mean reusability.

The SpaceX site [spacex.com] claims it is reusable, but I don't know if it actually has been reused to date.The last picture on the above linked page shows the condition of the returned vehicle. Its significantly crispy that it might be less expensiveto simply build a new one. Especially for manned missions coming later.

Dragon capsules are reusable, however, NASA has specifically contracted new capsules for every resupply mission. There's nothing stopping SpaceX from reusing the capsules for other missions, however.
I know the demo 1 capsule, that performed a few orbits before returning, and demo 2 capsule, the first to berth with ISS, are both hanging outside mission control at the SpaceX headquarters in Hawthorne, CA.

SpaceX has said that Dragon hardware from COTS missions will be refurbished for DragonLab missions. I'd be interested in seeing if refurbishing actually results in significant cost savings or not (I'm not a mechanical engineer, but I guess it depends on how much value is tied up in parts, versus labor).

That "crispy" look is just soot/ash from the heat shield. You can see several places below the channel for the drogue chute's cord (the diagonal groove) where it has been rubbed off, showing a pristine white underneath. Besides, that picture only shows the bad side of the capsule. Take a look [nasa.gov] at the capsule from a few different [space.com] angles [msn.com]. You see, contrary to popular belief, capsules like this do not traverse through the atmosphere straight on. They "fly" in a tilted orientation. That's why the soot marks are on an angle, and one side of the capsule looks charred, while the other looks barely singed.

The Dragon spacecraft/capsule is partially reusable. So far, the Falcon boosters are single-use. Space-X hopes to start recovering the first stage boosters, but that isn't working yet.

Meanwhile, they have 9 Merlin engines per Falcon first stage, one per second stage, and they're building about 400 per year. So they get manufacturing economies of scale. That's more valuable than reusability with heavy refurbishing, which tends to be a labor-intensive custom job. Refurbishing was the big cost problem with the US Space Shuttle - the amount of labor required for each turnaround was very high.

It's really a misnomer to call the space shuttle reusable. "Rebuildability" is more like it. The things had to spend months after each flight being torn apart and having every part inspected over and over and a big chunk of them replaced.
The key to economic space flight is full and rapid reusability. Payload launchers need to become as reusable as passenger aeroplanes for space flight to become routine.

you think that the small amount spacex is spending compared to the shuttle means its rockets are unsafe. what it actually means is its a good design, which costs a lot less to make safe compared to the shuttle, which is a bad design, that cost a incredibly large amount of money to make sorta, kinda, not really, safe.

The Dragon's are designed to be reused. However, if I recall correctly, NASA requested that SpaceX use a brand new capsule for each of the 12 scheduled delivery missions. This likely means that SpaceX is building up a stock of used Dragon capsules that can be repurposed to other missions at a reduced price.

If someone could confirm this, I would like to know if this is because NASA is stuck in the old ways of doing things with capsules, or if there is a legitimate safety/efficiency reason used Dragons could not be recycled for future supply missions.

Outside of California you'd have Ivy league types figuring out ways to pay the engineers nothing while paying themselves close to 1000x the average engineer. Like it is done everywhere but in crazy CA.

A huge move forward for private space flight. The fact they had a major problem and still achieved the goal was a huge move forward for private space missions. Private companies are becoming a viable alternative to NASA.

SpaceX built and lauched the rocket into an initial orbit, had a problem with the capsule's booster's supply of propellant that they were able to fix, and delivered the capsule to the right point, orbiting alongside ISS within reach of it's Canadarm, a little later than originally scheduled.

In what way did SpaceX not succeed? And who, in your opinion, was the party who 'saved' this mission?

I agree that, while SpaceX is establishing a good record of recovering from issues, it would be better if they could develop a record of not having issues!

The fact Russia didn't ass-rape us over the cost this time is always a viable alternative. They took advantage of the situation of us not having a Shuttle and we (NASA/American public) knew it! Screw those guys. I'll take SpaceX any day of the week over them.

The next time you get into a car, if your brain is messed up somehow, might you crash into a school bus? If you crashed hard enough into the school bus, I don't know if the kids in the school bus could survive.

Progress M-34 undocked from Mir at 10:22:45 UTC on 24 June, in preparation for a docking test planned for the next day. On 25 June, the spacecraft re-approached Mir under manual control, in a test intended to establish whether Russia could reduce the cost of Progress missions by eliminating the Kurs automated docking system. At 09:18 UTC, whilst under the control of Vasily Tsibliyev, the Progress spacecraft collided with the space station's Spektr module, damaging both the module itself, and a solar panel.[4] Following the collision, Progress M-34 was manoeuvred away from the station, before being deorbited on 2 July.[6] Its deorbit burn was conducted at 05:34:58 UTC, with the spacecraft being destroyed during reentry over the Pacific Ocean at 06:31:50.[5]

Ho lee fook, that sounds like a Chernobyl type scenario all over again. Turn off automated safety systems for some sort of harebrained manual test and surprise surprise, they run into problems.